1. Field of The Invention
The present invention relates generally to an improvement on an analog indicator. More particularly, the invention is directed to an analog indicator including a self-luminescent pointer and a fluorescent display plate which may be employed in a tachometer, a speedometer, a fuel gauge, a temperature gauge, or so forth for an automotive vehicle.
2. Description of The Prior Art
U.S. Pat. No. 5,050,045, issued on Sep. 17, 1991, assigned to the same assignee as the present application, discloses a self-luminescent pointer device for a gauge such as an automotive speedometer. This conventional pointer device includes an indicating pointer provided with a discharge lamp about which a light insulating film is wrapped exposing part of an upper surface to define a slit-like transparent section. Turning on the discharge lamp causes the slit-like transparent section to glow so that an observer, or vehicle operator may visually perceive displacement of the pointer over the display plate.
Additionally, in a modification of the above arrangement, a slit-like transparent section is also formed on a side surface of the discharge lamp to illuminate an area on the display plate to define a strip-like illuminated portion which is shifted toward a low-speed indicating zone from the indicating pointer.
The above prior art pointer device, however, raises a drawback in that while the indicating pointer can be seen in the dark by its own glow, the brightness of an area around notches graduated on the display plate may be insufficient for the observer as the display plate is illuminated by the light only projected from the indicating pointer.